Vacuum breaker



Oct. 13, 1953- lJ, J, CAN-TOR 2,655,171

VACUUM BREAKER Filed Aug. 29, 1947 2 Sheets-Sheet 1 L as r9-i6 155 p .3.J4 9 J0 j, 14 Je 15 156 0 15/ 15a. w j@ 15C Jga ,1a

la n INVENTOR.

g BY

. TTOZNEV oct. 13, 1953 JQ J, CANTOR 2,655,171

VACUUM BREAKER Filed Aug. 29,' 1947 2 Sheets-Sheet 2 IN VEN TOR.

BY @1M/WMM Patented Oct. 13, 1953 UNITED STATES PATENT OFFICE VACUUMBREAKER Jacob J. Cantor, Los Angeles, Calif. Application August 29,1947, Serial N o. 771,172 4 Claims. (Cl. 137-218) This invention relatesto valve structures, commonly known as vacuum breakers, adapted forinstallation in water or other liquid supply systems to preventsiphoning of the liquid from a point of use back into the system, inresponse to the creation of a vacuum therein.

It is an object of this invention to provide an improved valve structureof this type.

Such valve structures usually include a liquid inlet valve, a liquidoutlet, and an atmospheric inlet valve. As long as the liquid supply ismaintained, the liquid inlet valve is open and the atmospheric valve isclosed. If the liquid supply fails, the liquid inlet valve closes toprevent reverse now through the inlet, and the atmospheric valve opensto admit air to the outlet and` break the suction therein created by thebackward movement of the liquid in the system.

Itis another object of this invention to provide an improved form ofatmospheric valve for vacuum breakers.

It is another object of this invention to provide an improved valveclosure wherein misalignment between the closure and its seat does notimpair the effectiveness of the seal.

It is another object of this invention to provide an improved float foroperating the air and water inlet closures in a vacuum breaker.

It is another object of this invention to provide a, vacuum breakerhaving improved means for guiding the float.

It is another object of this invention to provide a vacuum breakerwherein the iloat is so arranged that solids or foreign matter carriedby the liquid will not render the float inoperative.

It is another object of this invention to provide a vacuum breakerwherein operation of the device to relieve a. Vacuum will not render theat. mospheric valve inoperative to close.

It is another object of this invention to provide a vacuum breakerhaving an improved atmospheric valve, so -arranged that a small quantityof liquid flowing through the vacuum breaker serves to close the valve.

It is another object of this invention to provide a vacuum breakerwherein the atmospheric valve will not be held open by the suctioneffect of Athe outlet when more liquid is leaving the vacuum breakerthan Ais entering.

This invention possesses many other advantages and has other objectswhich may be made more easily apparent from a consideration of severalembodiments of the invention. For this purpose there are shown a numberof forms in the :drawings accompanying and forming part of the presentspecification. These for-ms will now be described in detail,illustrating the general principles of the invention; but it is to beunderstood that this detailed description is not to be takenin a,limiting sense since the scope of the invention is best defined by theappended claims.

In the drawings:

Figure 1 is an axial section of a vacuum breaker incorporating featuresof the invention;

Figure 2 is a cross section, taken substantially as indicated by line2-2 of Figure 1;

Figure 3 is a fragmentary axial section on an enlarged scale showing theatmospheric valve closure in closed position;

Figures B-a, 3-b and 3-c are axial sections showing modified forms ofatmospheric valve closures;

Figures 4, 5 and 6 are views similar to Figure 3, showing otheroperating positions of the valve closure;

Figure 7 is a view similar to Figure 3, but showing another modifiedform of valve closure; Y

Figures 8 and 9 are views similar to Figure 7, showing other operatingpositions of the closure;

Figure 10 is a cross section similar to Figure 2, but showing a modifiedform of vacuum breaker; and

Figure 11 is a view similar to Figure 3, but showing a further modifiedform of atmospheric valve closure.

Referring to Figures 1 and 2, the vacuum breaker comprises a cylindricalbody I having a vertical axis and forming a chamber 2. The lower end ofthe body l is closed by an integral head 3 having a liquid inlet port 4therethrough, coaxial with the body l and surrounded by an annular valveseat 5. An interiorly threaded, external boss 6 is provided on the head3 for connection with a liquid supply pipe G-a.

The upper end of the body I is closed by a head 1 threaded into the bodyI against a shoulder 8 provided with a suitable gasket. The head 1 has acentral opening 9 coaxial with the body I, forming the air inlet, andspanned by a diametral bar l0 which supports a depending axiallydisposed guide pin or rod II. A pair of bosses I2 at the edge of opening9 on opposite sides of the bar l0 serve to mount a cap I3 secured as bydrive pins I4. The cap I3 protects the -air inlet 9 against direct entryof undesirable solids, dust and the like, at the same time freelyadmitting air.

A closure l5 of novel form is `provided for the air inlet 9 andcomprises a resilient saucer-like body or disc l5a. of rubber forexample. with an upstanding peripheral ange or rib IS-b adapted to seatand seal against the bottom surface of the head 'I about the opening 9.The closure I is mounted on top of a float member I6 and in spacedrelation thereabove. In this way, the body I5-a is adapted for limiteduniversal movement with respect to the supporting float IB, as will bemore fully pointed out hereinafter.

The closure for the inlet port 4 comprises a light disc I'I of metal orthe like, which is urged against the seat 5 by gravity.

The float I6 is interposed between the closures I5 and II, and has upperand lower cylindrical portions IB-a and IB-b of diierent diameters, theupper portion IS-c being of larger diameter and joined to the lowerportion IS-b by a downwardly facing annular shoulder IG-c. A float ofthis type when substantially submerged has greater buoyancy at its upperend, andaccordingly tends to remain upright and to move in a verticaldirection, thus simplifying the problem of providinga suitable guide.The opposite ends of the oat I5 are closed appropriately, an axial tubeI8 extending upwardly from the bottom of the iloat and through the topwall, serving to mount the closure I5, and having an upper end portionof reduced inside diameter as indicated at I8-a, which slidingly engagesthe guide pin II. This reduced portion IB-a provides sufficientclearance about the pin II to insure free movement of the neat IB inresponse to changes in the liquid level, as vwell as to permit limitedmisalignment between the iloat I6 with respect to the pin I I and theseating surface on the head 1. However, the length and diameter or thebore I 8-a is so proportioned with respect to the diameter and length ofthe pin II as to restrict such misalignment so that the end of the pinIl can at no time engage the interior surface of the tube I8 andpossibly restrict or prevent movement of the float I6.

The bottom of the iioat I6 has a circular extension IS-d of suchdiameter as to provide a seat for the lower end of the tube i8 and whichserves to support the oat I5 on the closure I1 when there is no liquidin chamber 2 to support theloat.

As shown in Figure 3, the tube I8 extends above the top of the float I5for mounting the closure I5. 'I'hus the closure body I5-a may beprovided with an integral hub I5-c on its lower side, the tube I8passing through an opening in the hub and the body, and having a flangeIB-b at its upper end for confining the hub I5-c against the top of thefloat I6. The hub I5-c serves as a spacer to maintain the body I5-aspaced above thefloat.

It is not necessary to provide an integral hub as I5-c to maintain theclosure body I5-a spaced above the float IS. Thus as shown in Fig. 3a, aspacer 30 may be provided which is in the form of a ring. This ring maybe of metal or other suitable material and may be merely conned betweenthe closure body Iii-a and the top of the float I6, or may be secured tothe iloat. In Figure S-b, the body IES-a is shown as secured at anappropriate distance above the float I6 as by being vulcanized to thetube I8, as indicated at 3i.

The body I has a side outlet 2D adjacent its lower end, an internallythreaded boss 2I being provided for connecting a suitable pipe orconduit 2I-a with the outlet 20.

A cylindrical wall or baie 22 is secured to the bottom head 3 about theinlet 4 within the chamber 2, extending across the outlet 2t, andforming a well 23 for accommodating the float IB. A small drain port22-a is provided in the wall 22, near its lower end.

In operation, liquid enters at 4, raises the Valve closure Il', ows intowell 23, and raises float I6, together with flexible closure I5, thefloat I5 being guided by guide rod II. Valve I5 occludes atmosphericopening 5. The major portion of the water spills over rim of wall 22 andleaves the vacuum breaker through outlet 20.

Referring to Figure l, it will be noted that the pin II is effectiveonly to guide the upper end of the float i6. The lower end oi the floatis steadied and directed by the force of the water conned and directedupwardly by the wall 22.

Upon cessation of the liquid flow through the inlet 4, the closure I'I'will seat and substantially all liquid above the level of the wall 22will pass directly out through the outlet '20. Liquid in the well 23will pass out through the aperture 22-a. This prevents any lateral forceacting upon the bottom of the float I6 and tending to draw the floattowards this opening 20. The importance of this action is apparent whenthe now oi liquid into the vacuum breaker is intermittent.

Under conditions of intermittent flow, especially when liquid is'flowing from the outlet 20 at a rate greater than that at which it isentering through the inlet 4, the 'balile or wall 22 prevents the oat IBfrom being drawn towards the outlet 20 and held by the suction effect ofthe outgoing liquid. Under such conditions, if the wall 22 were notpresent, the buoyancy of the float I'S would not be sufficient toovercome the force of the suction holding the float I6 against theoutlet 2D. 'Ihus the atmospheric Valve would be held open. A surge ofincoming liquid under such conditions would rise above the float I6 andilow out through the atmos* pheric opening 9.

The opening 22-a acts as a drain for removing any liquid remaining inthe well 23 after liquid ceases to enter the inlet 4. Since the opening22-a is always below the level of the bottom of the iloat I6 and is ofrestricted size, the liquid discharging through it can exert littlelateral force on the float I6. The float I6 is therefore free from thesuction produced'at the outlet 2l! and is always freely buoyant.

If desired, a baffle of limited extent may be provided across the outlet20 for preventing the lateral movement of the ilcat IIB due to thesuction at the outlet 20. For example, referring to Figure l0, anarcuate wall 28 of substantially degrees extent is shown in lieu of thecylindrical wall 22 of Figures l and 2. Otherwise the structure ofFigure 10 is substantially identical with that of the rst described formof the invention.

The shape of the oat is such that the force of the confined liquid inthe well 23 impinges on the bottom and shoulder Il-c of float I6. As theiloat rises, the area available for the passage of liquid is materiallyincreased.

As previously pointed out, the tube I8 in the float I6 is a loose t onthe guide pin II, so that the float I6 may be substantially misalignedwith respect to the air inlet 9, a particular feature of the closure I5being that it will effectively seal the inlet 9, regardless ol suchmisalignment, and will permit variations in the angular relationshipbetween the closure and the oat, due to the liquid dow in chamber 2.

A diiiiculty sometimes encountered in prior art vacuum-breakers, is thefailure of the valve at the atmospheric opening to remain closed duringlow variable .water pressures. This is due to the eddying currents,acting upon the float I6 and pulling a portion of the valve inarginsI5-b 01T its seat, with the result that liquid can pass through thisopening and escape through the. atmospheric Opening 3.. v

Besides directing the liquid directly upward by means of the wall or''baille' 22, the' float member ISfis so ldesigned that its greatestIbuoyancy is at its upper end, causing it to be less affected by theminor veddying currents' present in theliquid in the chamber 2. Any eddycurrents not taken care of by the wall 2'2 andthe particular shape ofthe float I'S, are taken care of by the novel relation between the floatI6 and the valve member I5. Thus, the closure I5 being spaced away forthe top of the float I6 will remain in contact with its seat on the headl, even though the float I6 may move through a considerable angle withrespect to the seat. 4This is due to the flexibility of the cenr tralportion of the closure body I5-a.

Figure 3 shows the closure I5 seated in response to relatively lightupward pressure by the float I6, the float being substantially alignedwith the inlet 9. The narrow peripheral rib I5b cooperates with theinner vsurface of the head 'I to seal about the inlet `9. However, theresilience of the closure i5 is such as to maintain an effective sealunder conditions of substantial misalignment, such for example as shownin Fig. 4. Thus the need for accurately guiding the float I 6 isavoided.

In response to increased upward pressure on the float I6, the centralportion of the closure I5 will be forced upwardly so that in addition tothe seal provided by the peripheral rib I5-b, a second seal is providedat 'S, between the lower edge of the closure I5 and the top of the floatI6, as shown in Figure 5.

If sufficient upward force acts on the float I6, the peripheral rib I5-bwill be flexed outwardly and the outer portion of the closure I5 will beconned Abetween the top of the float and the under face of the head 9,as shown in Figure 6'.

It will be apparent from an inspection of Figure 5, that the seals at Sand about the tube I8 cooperate toform an annular sealed space T, inwhich air and liquid is trapped. As the float I6 moves upwardly to theposition of Figure 6, the volume of this space T is substantiallyreduced so that the air therein is compressed. Thus when the upwardforce on float I6 is released, this trapped air urges the floatdownwardly, insuring quick opening of the port 9.

It may be desirable to provide an atmospheric inlet closure which isless yieldable than the closure I5 just described, but which will stillaccommodate misalignment as well as angular movement of the oat I6. Sucha closure is shown in Figure 7 and comprises a body 25-a which may beformed of material similar to that in the previous form and having aperipheral ange 25-b and means to maintain the body spaced above thefloat I6 such as an integral hub 25-0, all as before. In this case,however, a lat ring 26 of stiff material is moulded in the body 25-a,the central resilient portion of the body 25-a within the opening of thering 26, and the hub 25-c sufiicing to allow limited universal movementbetween the iMesure 25 and the 1103i?! I6, to permit seating of theclosure, asshown in Fligure 8,v or to form a double seal as shown ,inFigure 9.

As in the first described form of atmospheric inlet closure, the body25-a may be maintained spaced `above the float by a separate spacerring, or by being secured to the tube I8.

In Figure 3-0, a valve closure 3'5 is shown which is quite similar tothe first described form ofclosure I5, having a resilient body 35-a ofrubber or the like, with a peripheral upstanding rib 35- b and a centralintegral hub 35-c. However in this form of closure, the body 35-a is ofreduced thickness immediately about the hub 35-c, so that a centralannular portion is provided which is sub-'- stantially weaker or lessresistant to flexing than the outer portions of the body. Thisfacilitates the accommodation by the closure 35 while in closed positionof any misalignment between the float I6 and valve seat on the head 1,as well as the simultaneous sealing against the seat and against thefloat I6 in a manner similar to that shown in Figure 5.

In Figure 1l, a form of atmospheric valve is shown which is especiallysuitable for use with hot liquids. A modified form of head 31 is usedwhich is identical with the head I except for the provision of anannular depending rib 37-a forming a seat above the opening 38. Theclosure member 39 comprises a thin disc 4D of light gauge sheet metal ora suitable plastic, having a central aperture dil-a for accommodating areduced portion or neck 4I of a hub 42. This hub 42 is mounted on anextension I8-c of the tube I8, which is threaded to receive a nut 43securing the hub 42 in place on the float IB.

The hub 42 is formed of an appropriate material such as a plastic orrubber compound, which is sufliciently resilient to allow universalmovement and/or misalignment between the seat 3'l-a and the float I6,while the closure 39 is maintained seated by the float, in a mannersimilar to that discussed hereinbefore.

A closure arranged in the above described manner enables the use ofcertain materials having important advantages, such as high seattolerance, which are not Well adapted for forming the previouslydescribed types of closures.

I claim:

1. In a vacuum breaker, means forming a chamber having air and liquidinlets at its upper and lower end respectively, as well as an outletadjacent said lower end, a closure for each of said inlets, the closurefor said liquid inlet operating automatically to prevent reverse liquidflow, a oat 'disposed in said chamber for vertical movement to operatethe air inlet closure, and means restricting flow from said chamberthrough said outlet to cause operating movement of said float inresponse to a small flow of liquid through said liquid inlet. i

2. In a v-acuum breaker, means forming a chamber having air and liquidinlets at its upper and lower end respectively, as well as an outletadjacent said lower end, a closure for each of said inlets, the closurefor said liquid inlet operating automatically to prevent reverse liquidflow, a float disposed in said chamber for vertical movement to operatethe air inlet closure, means forming a well to receive the liquid fromsaid liquid inlet, and accommodating said iloat, to cause operatingmovement of said float in response to a small flow of liquid throughsaid liquid inlet, and means for draining said Well upon cessation ofliquid flow.

3. In a vacuum breaker, means forming a chamber having an air inlet inits upper end, a liquid inlet in its lower end, and a side outletadjacent its lower end, a closure for each of said inlets, the closurefor the liquid inlet operating automatically to prevent reverse flow,means forming a vertically extending well about said water inlet, afloat disposed in said well for vertical movement to operate the airinlet closure well, the wall of said well serving to restrict lateralmovement of the float; and means for draining the Well 4. In a vacuumbreaker, means forming a chamber having an air inlet in its upper end, aliquid inlet in its lower end, and a side outlet adjacent its lower end,a closure for each of said inlets, the closure for the liquid inletoperating automatically to prevent reverse ow, a vertical wall extendingabout said liquid inlet and forming a well, a oat for operating the airinlet closure, disposed in said chamber and said well for verticalmovement, and having an enlarged upper portion extending into said well,and providing a downwardly directed shoulder, liquid from said inletentering said Well and flowing over said Wall to the outlet, saidenlarged oat portion cooperating with said wall to provide a constrictedannular opening for liquid flow from said well, movement of said oat toinlet closing position causing said enlarged portion to be spaced abovethe Well providing an enlarged opening for said water flow.

JACOB J. CANTOR.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 257,853 Dibble May 16, 1882 603,592 Buckingham May 3, 1898839,855 Jones Jan. 1, 190'? 920,556 Fitts May 4, 1909 1,424,756 DeanAug. 8, 1922 1,452,999 Brier Apr. 24, 1923 1,506,012 Lewis Aug. 26, 19242,103,05.7 Blumer Dec. 2l, 1937 2,116,592 Bassett May 10, 1938 2,252,164Cantor Aug. 12, 1941 2,313,773 Samiran Mar. 16, 1943 2,325,956 HoltmanAug. 3, 1943 2,332,695 Cantor Oct. 26, 1943

